21338441 has 2 divisors, whose sum is σ = 21338442. Its totient is φ = 21338440.

The previous prime is 21338437. The next prime is 21338467. The reversal of 21338441 is 14483312.

It is an a-pointer prime, because the next prime (21338467) can be obtained adding 21338441 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15768841 + 5569600 = 3971^2 + 2360^2 .

It is a cyclic number.

It is not a de Polignac number, because 21338441 - 2² = 21338437 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21338441.

It is not a weakly prime, because it can be changed into another prime (21338431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10669220 + 10669221.

It is an arithmetic number, because the mean of its divisors is an integer number (10669221).

Almost surely, 2^21338441 is an apocalyptic number.

It is an amenable number.

21338441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21338441 is an equidigital number, since it uses as much as digits as its factorization.

21338441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2304, while the sum is 26.

The square root of 21338441 is about 4619.3550415615. The cubic root of 21338441 is about 277.3666420882.

The spelling of 21338441 in words is "twenty-one million, three hundred thirty-eight thousand, four hundred forty-one".